1. Field of the Invention
The invention relates to a wire-cut electric discharge machine and particularly to a wire-cut electric discharge machine having a workpiece measuring function of measuring, by using a machining program, a shape of a workpiece machined by the machining program.
2. Description of the Related Art
Machining accuracy of a workplace machined by a wire-cut electric discharge machine may be checked by 1) measuring the workplace by a micrometer, 2) detaching the workpiece from the machine and attaching it to a measuring device disposed apart to measure it, or 3) preparing a measuring program corresponding to a machining program to measure the workpiece, after machining of the workpiece.
As techniques related to the above 2) and 3), there is a technique of a self-correcting machining method for bringing a touch probe into contact with a machined workplace from an optimum direction and carrying out correcting machining of the machined workplace based on obtained measurement values as disclosed in Japanese Patent Application. Laid-Open No. 6-190685.
In both of the above cases of 1) and 2), a worker needs to be there between the end of the machining and the measurement. Especially, the case of 2) requires preparation of detachment and attachment of the workpiece and takes many man-hours. To automate checking of the workpiece machining accuracy, it is necessary to dispose a workpiece moving means such as a robot, which scales up a system configuration. Although the checking can be automated and made unattended in the case of 3), it is necessary to create a measurement program every time the machining program is updated, which is much trouble.